Currently, as a technology which enables with ease a high speed, miniaturization, and an increase in the size of copying machines and laser beam printers (hereinafter, “LBP”), an electrophotographic photoreceptor belt wherein the electrophotographic photoreceptor is formed in the shape of a belt has been developed.
The electrophotographic photoreceptor belt has an advantage that a metal drum having a large diameter as conventional photoreceptors is not required and a wider photoreceptor can be developed in the same volume. Therefore, it is suitable for miniaturization of an equipment and high-speed printing of a large-sized print such as a poster.
The mainstream of an electrophotographic photoreceptor belt is that wherein a photosensitive layer (a photoconductive layer, or in case when it is of multilayer type, a charge generating layer and a charge transport layer) is formed on a conductive support belt substrate such as a film of stainless steel or an aluminum metallized polyethylene terephthalate to form an electrophotographic photoreceptor belt. Among them, an electrophotographic photoreceptor belt wherein polycarbonate is used for a photosensitive layer, particularly for a charge transport layer is known (see Patent Document 1 and Patent Document 2).
These electrophotographic photoreceptor belts are required to be exchanged after copying on a certain number of paper since it is worn and deteriorated by friction of a transfer belt, paper, a cleaning blade or the like. However, in case when an operator touches with bare hands at the time of exchange, it may occur that cracks begin to generate at the touched point to cause shortening of a service life of the belts, and thus there is a room for improvement.
Patent Document 1: Jpn. Pat. Laid-Open Publication No. H6-236045
Patent Document 4: Jpn. Pat. Laid-Open Publication No. H10-111579